"My biggest qualm with BART is how crowded the trains can get. I really wish the city would update the seating arrangement; when I was living in Asia, I noticed all of the trains would fit way more people than BART does because they had more space for those standing and benches that faced inward as opposed to BART's chairs facing the front/back of the train."

A crash Friday morning in Concord killed a 37-year-old man who was ejected off of his Harley-Davidson motorcycle and crushed to death under an SUV, authorities said.

The collision occurred at 6:43 a.m. near just south of Concord Avenue on the southbound lanes of Highway 242, according to the California Highway Patrol. Authorities said an initial investigation found that the motorcyclist was riding a Harley-Davidson Road King and was splitting lanes in heavy traffic, but for unknown reasons the rider suddenly slowed and veered from the left lane into the second lane, where his motorcycle crashed into the back of the Infiniti.

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The man was reportedly thrown off the bike and lodged beneath the other vehicle. A pregnant woman driving the Infiniti SUV stopped, CHP said, but by then the rider was trapped underneath her vehicle and ended up being crushed to death.

Emergency responders helped remove the man and he was pronounced dead on scene.

The pregnant woman was not injured but was taken to John Muir Hospital in Walnut Creek for precautionary reasons, officials said.

Authorities were not sure if drugs or alcohol played a factor in the crash. Authorities have asked anyone who witnessed the crash or events leading up to it to contact Contra Costa CHP in Martinez at (925) 646-4980.